Reorganize tests to compare output against baselines

[christopherwharrop-noaa]

This update refactors tests so that their output is checked against correct results rather than simply relying on a successful run to completion. The test directory is separated into output/ and src/ where output/ stores the correct answers for the tests and src/ stores the source code of the tests. The CI workflow was updated to run the tests and then compare their output against the known baselines. This results in more robust testing.

[christopherwharrop-noaa]

@NaureenBharwaniNOAA - I finally got all the issues worked out. This is ready for you now.